1. Chapter Six: Chemistry in Biology 6.1 Atoms, Elements, and Compounds 6.2 Chemical Reactions 6.2 Water and Solutions 6.4 The Building Blocks of Life

2. 6.1 Atoms, Elements, and Compounds The building blocks of matter are __________. They are the smallest unit of matter. Composed of three _____________ particles. _______________: positively charged particles. _______________: neutral particles _______________: negatively charged particles. The protons and neutrons are contained in the ______________.

3. Elements & Periodic Table Pure substances that cannot be broken down into other substances by _____________ or _____________ means. Periodic table consists of rows, called _____________, and columns, called _____________. Atoms of the same element that have a different number of neutrons are known as _______________. Carbon-14 is an example of a _______________ ____________.

4. Compounds A pure substance formed when two or more different elements combine are called ________________. Water is ________. Sodium chloride is _______. Methane is ____________. Compounds cannot be broken down into simpler compounds or elements by _____________ means.

5. Chemical Bonds Electrons are shared in _______________ bonds. A ____________ is a compound in which the atoms are held together by covalent bonds. Single, double, and ___________ bonds can exist in covalent molecules. H 2, O 2, and N 2 are examples of each Electrons are either taken or given in _________ bonds. When an atom gains or loses an electron, it becomes an ________.

6. Trends on the Periodic Table Donators are on the __________. Acceptors are on the ____________.

7. Van der Waals Forces The attractions between molecules that hold them together. Strength of the attraction dependents on three things. ________ ___________ Ability to attract ___________. van der Waals forces allow water to form droplets.

8. 6.2 Chemical Reactions Process by which ________ or groups of atoms in substances are ___________ into different substances. Iron oxide is also known as _________, and is formed when iron reacts with oxygen. Signs of a chemical reaction include: Production of _________ or light Formation of a _________ or ____________.

9. Chemical Equations Reactants  Products The arrow can mean _________ or ________________. Reactants are the ______________ substances. Products are the substances formed during the reaction. C 6 H 12 O 6 + O 2  CO 2 + H 2 O Anyone know what this reaction is? Now we have to balance it!

10. Balancing an Equation C 6 H 12 O 6 + O 2  CO 2 + H 2 O Carbons:Carbons: Hydrogens:Hydrogens: Oxygens:Oxygens:

11. Activation Energy The minimum amount of energy required to make the reactants become products Example: you must light the wick of a candle before the candle will burn. What is the change in energy? Exothermic: ___________ Endothermic:___________

12. Enzymes Help ___________ the activation energy of a reaction. A ____________ is a substance that lowers the activation energy needed to start a chemical reaction. Enzymes are _____________ catalysts.